The invention relates to manually operable controls for electronic devices.
In the past decade a variety of electronic devices, including portable electronic devices have come into wide spread use. In the design of electronic devices that are portable emphasis is placed on reducing the space occupied by each individual component, and reducing the cost. The former consideration leads to selection of buttons that have a small stroke (distance the button moves when actuated). Unfortunately, such buttons do not provide a great deal of tactile feedback to a user operating the buttons. This is particularly problematic if a user is in the habit of actuating a sequence of buttons in rapid succession, in the case of user having reduced manual dexterity (e.g., an elderly user), or in the case of a visually impaired user.
Dome switches which abruptly displace when a certain threshold manual actuation force is exceeded, have been used. Although such switches provide a degree of tactile feedback, they have complex structures, and commensurate cost. Elastomeric switches are a type of low cost, but also, low stroke switch. Regrettably, elastomeric switches provide little tactile feedback.
Given the rapid introduction of new types of device (e.g., Personal Digital Assistants, Text messaging pagers, MP3 players), and the rapid development of novel functionality, another important objective in designing electronic devices is to provide intuitive interfaces. Employing touch screens along with graphical user interfaces (GUI) is one avenue to providing intuitive interfaces. Unfortunately, the stroke of touch screens is frequently so small as to be imperceptible, and consequently touch screens provide little if any tactile feedback.